micro electrode arrays meas  (Grainger Industrial)

Journal: Cell Death & Disease

Article Title: Tau P301L disengages from the proteosome core complex and neurogranin coincident with enhanced neuronal network excitability

doi: 10.1038/s41419-024-06815-2

Figure Lengend Snippet: All experiments were undertaken in DIV12 cultures cultured in CytoView micro-electrode array (MEA) multi-well plates using the Maestro-Pro MEA system (Axion Biosystems). A Each well contains 16 electrodes that can record local activity B Fluorescent microscopy shows DIV12 primary cortical neurons transduced with AAV-Syn1-eGFP and cultured on a micro-electrode plate. Scale bar = 275 µm. C An example of a raster plot, which shows firing over time, taken at baseline from untransduced neurons. Each row corresponds to an individual electrode. Action potentials are recorded as spikes (black lines) and this is termed ‘firing’. A burst (blue) occurs when multiples action potentials fire in rapid succession in the locality of an electrode; a minimum threshold is set at 50 spikes within 100 ms. A network burst was classified as at least 35% of electrodes recording bursts simultaneously; this shows that the neurons throughout the culture are connected. D Representative raster plots showing 60 s recordings of untransduced neurons at baseline and following treatment with 0.625 µM 4AP/12.5 µM Bicuculline (Bic). Baseline recordings show spontaneous firing and bursting. Treatment with 4AP/Bic stimulates synchronous and oscillatory firing across the well, as shown by a switch to network bursting. E 4AP/Bic treatment significantly increases activity and ( F ) burst strength ( t -test, **** P < 0.0001, n = 3 technical repeats). G Representative raster plots comparing neurons overexpressing eGFP, eGFP-Tau WT or eGFP-Tau P301L at baseline and following treatment with 4AP/Bic. H At baseline, the activity and ( I ) burst strength of neurons overexpressing eGFP-Tau P301L is significantly greater than those expressing eGFP or eGFP-Tau WT . Following treatment with 4AP/Bic, activity but not burst strength is significantly greater with eGFP-Tau P301L than eGFP or eGFP-Tau WT (two-way ANOVA with Tukey’s multiple comparisons test, * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001, n = 4 technical repeats).

Article Snippet: All experiments were undertaken in DIV12 cultures cultured in CytoView micro-electrode array (MEA) multi-well plates using the Maestro-Pro MEA system (Axion Biosystems).

Techniques: Cell Culture, Activity Assay, Microscopy, Transduction, Expressing

Journal: Communications Medicine

Article Title: AAV9:PKP2 improves heart function and survival in a Pkp2 -deficient mouse model of arrhythmogenic right ventricular cardiomyopathy

doi: 10.1038/s43856-024-00450-w

Figure Lengend Snippet: a Heatmap of RNA sequencing analyses from iPSC-CMs ( n = 1 for negative control, siNeg, and n = 3 biological replicates for siRNAs against PKP2, siPKP2) harvested on day 2, 4, 6, and 8, respectively, after siRNA treatment, highlighting effects on genes encoding components of the desmosome, sarcomere, and ion channels. b PKP2 silencing led to reduction in protein expression of DSP, JUP, DES, and MyBPC3 in response to reduced PKP2 protein (Western blot on the left panel, day 8, n = 2 biological replicates) and a trending reduction in SCN5A mRNA in response to reduced PKP2 mRNA (RNA sequencing reads from Fig. 1a). c PKP2 silencing resulted in disappearance of PKP2 and DSP protein from the cellular membrane (top two rows, day 10, n = 5 technical replicates; IXM confocal microscope; 25 µm) and cell disarray in patterned iPSC-CMs (bottom two rows, day 10, n = 3 technical replicates; Leica DMi8 microscope; 25 µm). Immunofluorescent staining: PKP2 in green, DSP in red, and nuclei in blue. d PKP2 silencing led to defective contraction as quantified by contraction velocity using Pulse video analysis (day 3 to 8, n = 12 technical replicates for each day, n = 2 biological replicates) (Curi Bio) . Average nuclear counts from live cells were used to normalize contraction velocity. PKP2 silencing led to ( e ) depressed beat period; depressed amplitude; depressed rate of propagation of electrical signal, detected as extracellular field potential signals from the cardiomyocyte monolayers using M icro e lectrode a rray (MEA) plates (day 4 to 10, n = 18 technical replicates for each day, n = 2 biological replicates) (Axion Biosystems) . Quantified data were presented as mean ± s.d. P value: Student’s t test. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: PKP2 silencing led to ( e ) depressed beat period; depressed amplitude; depressed rate of propagation of electrical signal, detected as extracellular field potential signals from the cardiomyocyte monolayers using M icro e lectrode a rray (MEA) plates (day 4 to 10, n = 18 technical replicates for each day, n = 2 biological replicates) (Axion Biosystems) .

Techniques: RNA Sequencing, Negative Control, Expressing, Western Blot, Membrane, Microscopy, Staining